Solenoid-controller.



P. W. SMITH. SOLENOID CONTROLLER.

APPLICATION FILED 11211.5, 1910.

1,022,707. Y Patented Apr 9,1912.

f. M 4 a g I am dtto'wmgyjg L p STATES PATENT OFFICE.

mN-K W. SMITH, OF WESTFIELD, NEW JERSEY, ASSIGNOR TO SUNIDH ELECTBIGCOMPANY, OF NEW YORK, N. Y., AGOBPORAT'ION OF NEW YORK.

SOLENOID-CONTROLLER.

Specification of Letters Patent.

Patented Apr. 9, 1912 Application filed April 5, 1910. Serial No.553,546.

To all whom it may concern I Be it known that I, FRANK W. SMITH, a

citizen of the United States, and resident of the town of \Vestfield,county of Union, and State of'New Jersey, have invented certainnew anduseful Im rovements in Solenoid-Controllers, of which the following is aspecification, reference being had therein to'the accompan ing drawing,in which- Figure 1 is a iagrammatic view of a motor, a motor startingsolenoid, and the controller device.

In starting electric motors having great 'inertia to overcome, andrequiring a considerable current over-load to move them, it has been thepractlce, heretofore, to 1nsert in the motor circuit enough resistanceto prevent the burning out of the motor eration, w ereby the resistancewill be gr'ad 1 the motor isreduced and consequently the armature whenthe current is applied, and

then cutting out the resistance by some form of a paratus having astep-by-step' opuall reduced as the motorspeed is accelerate ,"and theinertia of the mass to be moved by the motor is overcome, or the motorload otherwise reduced.

It is the main object of thisinvention' to provide a solenoidcontrolling means by means of which when the motor circuit is com letedthe movement of the solenoid core will retarded or stopped until theload on amount. of current taken by the motor is also reduced, thesolenoid core being permitted to complete its movement only when thecurrent taken by the motor hasbeen reduced to the desired extent. It is,of course,

obvious that the amount of current taken I force. 1

e the op of course, obvious that there may be many;

by\the"'motor may .be reduced in yarious ways. lVhen the inertia of theload is over come and the motor has increasedits speed the load thereonis reduced, and consequently the amount of current taken by it ismrrespondingly reduced. It is also ob vious that as the speed of themotorincreases there is a reduction in the amount of current taken bythe motor by reason of the .back pressure or counter-electromotive Itisthe ob'ect of this invention totake advantage of t is reductionv incurrent taken by the motor in whatever way it may be brought about, forthe purpose of control ration of the solenoid, auditis,

variations in the specific apparatus forearrying this invention intoeffect, and I therefore desire it understood that I am not tc be limitedto the precise construction shown and described, except as the same maybe the core whereby said core will move into the coil slowly, and at thedesired speed.

Pivoted to the solenoid frame are two contact levers 9 and 9 which carrycontacts 10 and 10 at their upper ends adapted to engage the fixedcontact 11, this latter con tact being electrically connected to thesource of supply and to the solenoid coil.

The contact levers are electrically connected to pole 1 of the vmotorarmature, as will be more fully hereinafter described.

Carried by the solenoid core at. its lower end is a frame 12, and insaid frame are arranged rollers 13. These rollers are arranged toengage'cams 14; and 15 formed on the inner sides of the contact leversat'the lower ends-thereof. The cam M is located near the end of itscontact lever, while the cam 15 is some distance above the cam 14:,

whereby one of the rollers 13 will first contact with the cam'l i, andthereby bring contact 10 into engagement with the con tact 11, the cam15 being operated upon at a later period, as will be more fully hereinafter set fort-in Contact lever 9 is connected to one polel of the motorarmature through the resistance coil .16 anda retarding coil 17, said'recarding coil being of large capacity topermit the motor current topass therethrough. The contact lever 9 is electrically connected to thesamepole of the motor armatnreas lever 9, as clearly shown in thediagram. The fields of the motor are connected through a shunt 18, withthe lever 9 Above the retarding coil 17 is pivoted a horizontal lever19, said lever being providedwith a threaded arm 20 inwhich is itsarranged a counterbalancing weight 21. The Hi said lever is drawndownwardlyaway from the balanced lever 'by it, "on the motor,

the contact or stop 22, the solenoid coil cir cuit will be through saidresistance, said cirquit being broken between the stop 22 and Theoperation of this apparatus may be briefly described as follows: Whenthe switch 24 is closed, current passes through the balanced lever19,-stop 22 and the solenoid coil, but not through the resistance coil25. By means of the weight 21 the lever 19 and the core 23 are nicelybalanced so that said lever will be normally in contact with the stop22, but may be readily drawn from stop 22 by means of the coil 17 andthe core 23. Upon the completion of the circuit through the solenoidcoil, the'core 5 will be' drawn'upwardly, said upward movement beingretarded to the desired extent by the dash pot 7. 'When the roller 13contacts with the cam 14, the upper end of the lever 9 will be throwninwardly to bring'the contact 10 into engagement with the rigid contact11. Current will then flow from the lever 9.through the resistance coil16, the retarding coil 17 to the pole 1 of the motor armature. Whencurrent passes through the retarding coil- 17, the core or plunger 23will be drawn downwardly into said coil thereby breaking the solenoidcoil circuit at the stop 22, and causing said circuit to be completedthrough t-he resistance 25. The resistance 25 is suificient to reducethe effective pull of the solenoid coil, and to thereby. prevent furtherupward movement of the solenoid core. The core and the sliding frame 12will, therefore, be held stationary after the said frame has been raisedabove the cam 14, the outwardly projecting part'of the cam 14 engagingunder the end bar of frame 12 and assisting the coil in maintaining thecore in its stationary intermediate posit-ion. This condition of theapparatus will be maintained until the load on the motor has beenreduced, and consequently the amount of current taken by the motor iscorrespondingly reduced. This reduction in current may be brought aboutby the motor over coming the inertia of the mass to be moved or by theactual reduction of the load or by the counter-electromotive forcedeveloped by the motor. It is clear that as the current flowing throu hthe motor is reduced the pull of pleted by the contacts first the coil 1will be correspondingly reduced, and when said pull has been lowered tothe desired extent. it will failto overcome the weight 21,- and saidweight will then throw lever 19 into engagement with stop 22, therebycutting out the resistance 25 and permitting the full current to flowthrough the solenoid coil. As soon as this occurs the solenoid coil willcomplete its upward movement, thereby causing contact lever 9 to swingin-; wardly and bring contact 10 into engagement with the fixed contact11. The motor circuit will then be completed through said lever 9, anddirectly to pole 1" of the armature motor, thereb cutting out theresistance coil 16 and t e retarding coil 17, and supplying the fullcurrent to the motor.

From the foregoin tarding coil 17 will gold thelever 19 away from thecontact 22 until the current flowing to the motor and through the coil17 has been reduced sufiiciently to so diminish the pull of the coil 17that the weight 21 will overcome it and swing the arm 19 into engagementwith the contact 22. It is manifestsolenoid will be inthat the operationof the termittent, and that the final step or movement thereof will bedependent upon the reduction of the current taken by the motor. It isalso clear that the interval between the completion of the solenoid coilcircuitand the cutting out of the resistance in the motor circuit willdepend entirely upon the time required to reduce the current flowin tothe motor through retarding coil 17 su ciently to release the core 23.

It will, of course, be understood that the solenoid retarding device maybe employed in many ways, and on any desired form of solenoid.

It is also clear that the motor circuit may be completed through theretarding coil in any suitable manner, the arrangement shown in thedrawings being merely by way of illustration. 1

It will, of course, be understood that by varying the position of theweight 21 on the arm 20 the amount of pull required to .move the arm 19from the stop 22 may be varied, and consequently the amountof reductionin current flowing through said coil to bring about the release the core23 will be correspondingly varied.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent is: 4

1. A controller comprising a solenoid coil, means connectin saidsolenoid coil .directly in circuit with t e source of supply, a core forsaid coil, a pair of contacts brbught toit is clear that the re- Igether bythe initial movement of said core,

a motor, a motorcircu'it adapted to be como erated by the solenoid core,a resistancean a controlling coil in said motor circuit, a

movable core excess of current is flowing through said motor circuit,means to return said solenoid coil circuit to its normal conditionwhenrthe current flowing through the motor circuit is reduced, and. tothereby permit the solenoid core to complete its movement, and

contacts operated by said core as it cont pletes its movement to out theresistance and the controllin coil from the motor circuit.

2. A solenoid controller comprising asolenoid coil, a single coremovable into and out of said solenoid coil, a pair of contacts arrangedto be closed or opened by the movements of said core, an operatingcircuit arranged to be completed by the said pair of contacts, aresistance and a controlling coil in said circuit, a core movable intoand out of said controlling coil, means moved by said core for cuttingresistance into the solenoid coilcircuit, means tending to return saidmovable means to its normal position to cut resistance out of thesolenoid coil circuit and operating against the pull of the controllingcoil, a second pair of contacts arranged -to be closed by the furthermovement of the solenoid core, this latter pair of contacts alsocompleting the operatmg circuit. and cutting out the resistance and thecontrolling coil, thereby reventing the subsequent re-in'troduction othe re. sistance into the solenoid coil circuit. o

3. A solenoid controller comprisih asolenoid coil, a singlereciprocablecore or said coil,:'acircuit for said coil, a pair. ofcontacts arranged to be closed by the movement of said core, a motorcircuit adapted to be com p'leted by the said pair of contacts, aresistance anda controlling coil in said motor circuit, a reciprocablecore in said controlling coil, movable means operated by said core forcutting resistance into the solenoid coil circuit, said means tendingalways to.) return'to its normal position, saidcontrolling coiloperating under anvexcess of cur-' rent to place resistance in thesolenoidcoil circuit and operating whenthe current .in the motor circuitis sufliciently reduced to cut the resistance from the solenoid circuitthereby permitting the solenoid core to continue its movement, anotherpair of contacts adapted to be operated by the subsequent movement ofthe solenoid core, this latter pair of contacts completing the circuitthrough the motor direct and perinanently cutting out the resistance andthe controlling coil of the motor, circuit.

4. A solenoid controller comprising a solenoid coil, a .core movableinto and out of said .coil, contacts adapted to, be closed by said coreat'diflierent points in its travel to close an electric circuit, andmeans in said circuit controlled by the movement of the solenoid corefor neutralizing the pull of said coil tothereby arrest the movement ofthe core before it has completed its movement, said meansoperating upona reduc tion of current in the circuit controlled by the solenoid torestore the solenoid to its normal act-ion.

5. The combination of a motor, a'solenoid coil, a circuit for said coilincluding means for opening and closing said circuit,

a core movable into and out of said coil,

' 6 A solenoid controller comprising a sole noid coil, a circuit forsaid solen id coil, a reclprocable'core movable into and out ofsaidcoil,a pair of contacts arranged to be brought together by the initialmovement of -said core into the coil, a motor circuit adaptedto becompleted when the saidpair of contacts are brought together by the saidcore, a resistance and a controlling coil in said motor circuit, amovable core for said controlling coil, meansin the solenoid coilcircuit ,and connected to the core of the controlling coil to placeresistance r in the solenoid coil circuit when an excess of current isflowing through the motor circuit said means returning said coil circuitto its normal condition when the current -flowing through the 'motorcircuit is sufiibrought together by this second movement of the solenoidcore said contacts completing the -motor circuit direct and/cutting outthe resistance and the controlling coil and thereby, permanently cuttingout the resistance from the solenoid coil circuit.

Intestimony whereof I hereunto aifix my signature in the presence of twowitnesses this 1st day of April, 1910.

FRANK w. SMITH.

